Signatures to be gathered either on a saddle conveyor or flat gatherer, eventually fed to the conveyor out of a pocket feeder, are received from the binder in a heavy, strap-bound pack. The pack is opened and the signatures arranged as a loose pack in a loader, representing the main supply. The signatures are withdrawn one by one from the supply loader and advanced as a stream to the ultimate pocket feeder where they are extracted one by one and collected on the gatherer sequentially one atop another, to complete the book.
One form of signature feeding machine for accomplishing this is disclosed in U.S. Pat. No. 4,177,982 granted to McCain Manufacturing Corp., the present assignee. In this form of machine, the signatures constituting the main supply are stacked on edge in the loader, the backbone down, like so many fence posts, one behind the other.
In another form, the signatures constituting the main supply are stacked flat, one atop another, like a deck of cards. This form is disclosed in U.S. Pat. No. 4,907,791, granted to the present assignee.
These feeders are extremely expensive. The binder company which purchases the feeders may require as many as one hundred, collectively involving a cost of well over one million dollars. Unfortunately, the bindery attendants do not always know in which form the bound signatures will arrive from the printer, usually a 30" stack. The signatures may arrive on a pallet in the fence-post array (horizontal pack) or they may be palletized as a vertical stack like a deck of cards, wire bound with end boards which have to be removed in either case.
The horizontal stack (U.S. Pat. No. 4,177,982) is easier to place or insert in a loader having feed belts substantially horizontal; the stack is simply raised by a forklift or hoist, the straps and end boards removed, and the stack lowered carefully onto the conveyor belts of the feeder. One trip only is required to unload the stack.
In comparison, if the stack is vertical, then the feeder is of different form, U.S. Pat. No. 4,907,791. In this instance, the signatures must be hand loaded piecemeal: repeated 6" hand-held bundles for example, placed in the loader one atop another until the pallet is emptied, involving several trips, or several attendants to service the job.
Therefore, to cope with both possibilities, the bindery needs to stock both kinds of feeders, constituting a considerable expense, to say nothing of the storage space which must be accorded.
The primary object of the present invention is to construct a unitized signature feeder which will serve both circumstances, either for signatures set on edge in the loader, backbone down, or set flat one atop another.